Brake-shoe.



S. P. BUS

RAK H ION ,1908.

APPLI Patented 0011221908. ZSHEETS-SHEET S. P. BUSH.

BRAKE SHOE. APPLIOATION FILED JAN. 21, 1908.

Patented 0511.27, 1908;

2 SHEETS SHEBT 2" stirru STAQESLPATENT orrioa.

BRAKE-sires,-

No. 902,206; Specification 01 Letters Patent. Patented Oct. 27,1908

Application filed January 21, 1908. Serial No. 411,995.

To all whom it may concern: with the throat of the wheel takes place. Be1t.know n that l, SAMUEL Pnnsoo'r'r Examination of carwhecls broken inservice Bus a citizen of the United States, residhas shown in myexperlence almost invar1- mg in Columbus, in the county of Franklin ablythe presence of heat, which is apparent and State of Ohio, have inventedcertain from the oxidizationlof the metal atthe new and usefulImprovements in Brakepoint of fracture. It is apparent that the Shoes,of which the following is a specificahomogeneity of the metal of thetread and tion. I flange, es ecially at the throat, is destroyed Thisinvention has'particular reference to by these 'orces tending to producefracture,

10 the construction of a form of brake shoe and the lateral force towhich the flange relieve the weakest p0 which will prevent theapplication of the is subject in service hdds'to the severity of sho'etocertain portions of the wheel and the the conditions, the mechanicalconnection befiangc of the wheel to which it is applied tween the flangeand tread becomes readilyfrom time to time in service, and so willbroken. In the case of steel tired wheels rtion ofthetread of .there isseen an actual displacement of the the wheel and adjacent port-ion ofthe flange hard superficial metal of the tread into the thereof fromcontact with the said shoe, and softer metal lying adjacent thereto inthe which will avoid as far as possible ,the heat tire, and a forcingoutward of such softer ing, abrading and compressing strains. to metalinto the tread .proper. This is espezo which these weakest port-ionsofthe wheel cially true of the throat portions. are subjected when abrake" shoe of the ordi In the practice of my 1nvent 1on, I carry narycontour is used. out the plan illustrated in the accompany- Under thebrake shoe practi e usually carin}: drawings, wherein-e riedout, it isto-be noted that normally the Figure 1 1s a plan VIEW- of the Wearingshoe contacts with practically the entire face of a flanged brake shoeshowing my im- 8 0 tread of the wheel, including generally the provedformof construction; throat of the wheel and those portions of Figure 2is a sectional elevation taken on the trcad'adjacent the flange and ofthe base the line II-II of Figure l; 1

of the flange adjacent. the throat and tread, Figure 3 is a plan View ofplain ('un- 30 or a ma or part thereof, that is to say, the flanged)driver or car-shoe showing my im parts of the tread and flange which arein proved form of construction;

more or less continuous contact with the rail Figure 4 is a sectionalelevation taken on head; the line IV-IV ofFigure 3; It is wellknown tothose skilled in the, Figures 5, 5; 6, 6; 7 7; 8, 8; 9, 9-; 10,

3 5 :art that a large percentage of the failures 0 n 11a a d fi types 0f8 8 f il (my d i e h el Occur having my improved form of constructionthrough broken wheel flanges, and observailustrated therein, the firstand second mem tion has conclusively shown that most of bers of thepairs being respectively sectional such failures occur not throughflanges that and partial plan views of such shoes, the sec- 46 aredefective primarily in themselves, but tional views in each instancebeing taken on on account of the concentration of heavy the lineindicated by acorresponding Roman loads and heat at the tread of thewheel at numeral in the plan views.

and. adjacent the throat, excessive forces. Referring to theconstruction of shoe arise/from the load and heat stresses that marked A(Figures 1 and 2) t Will be seen areset up, which the metal of the wheelis that the inner portion of the wearii face of 1 00 not able towithstand. This concentration the shoe-that part adjacent the wheel isespecially apparent in the case of new flangehas been so formed as toavoid conbrake shoes applied to new wheels, Where tact with the throatregion of the Wheel F by reason of the coning of the wheel tread(indicated by dotted lines at the point marked 0 the shoe contactspractically at the throat of D) and the adjacent portions of the treadthe wheel alone, and further in the case of and flange receiving thegreatest wear in the application of new shoes to wheels the service fromthe rail head, marked C and J tread of which have become somewhatrespectively. This construction has been atgrooved in service fromcontact with the tained by removing a portion of the usual 5 rail head,where a like undesirable contact Wearing surface D, at E, between thesides service.

as are shown in Figures 2 and 5, strengthen-.

short distance along the outer may be of full width according tostandard practice, and adapted tobe" connected with the usual type ofbrake-head; and, second, for purposes of reinforcement and strengtheningthe back, to avoid fracture thereof in In. the flanged types of shoessuch mg ribs, M, M, may be provided to prevent the flange, Q, Q. frombreaking away from the back K, K, of the shoe. These strengthening ribsor brackets may be distributed along the back of the shoe at such'pointsas will not interfere with the brake head.

R-e:ferring to Figure 6, it will be noted that I have provided aprojecting guide by which the shoe maybe maintained at the distancedesired away from the flange of the wheel. This guide may extend theentire length of the shoe as indicated at L (and at L in Figure 10, andat L in Figure 11,) or one or more similar guides of short length may beplaced as convenient along the edge of the shoe as indicated at L inFigure 7 (and at L in Figure 9). For like strengtl'iening purposes asthe ribs or brackets M, opposing brackets may be placed on the innersurface of the flange Q, such as shown at N in Figure 5, and on theinner surfaces of the guide or guides as shown in Figures 9 and 10.Referring to Figures 8 and 11 it will be seen that I have illustrated myinvention as applied to the type'of shoe often .used with bald orunflanged driver wheels, wherein the wearing face of the shoe isextended as at P edge of the wheel R Figure 8, and at P and R in Figure11.)

It is obvious that theinvention above described, with reference to theamount of reduced wearing surface, or the proportion that such surfacebears to the back of the shoe, may be varied materially, withoutdeparture from the spirit of my invention, and

therefore I do not restrict myself to any of the details ofconstruction, or to the particular dimensions or arrangements, shown.

Having thus described my invention, and illustrated its use, what Iclaim as new and desire to secure by Letters Patent is the following:

1. ,brake shoe comprising a flange engaging portion, a rim engagingportion spaced away from the flange engaging portion to avoid contactwith the throat of. the wheel and a plurality of stiffening ribs on thefront of the shoe adjacent the throat.

2.- A brake shoe comprising a flange engaging portion, a rim en agingportion, an intermediate portion cut back to avoid contact with thethroat of the wheel anda plurality of ribs partially bridging the cutback portion.

3. A brake shoe having its face cut away at the throat of the aplurality of ribs cut away portion.

wheel and provided with partially bridging such.

I 4. A brake shoe having its face cut away at the throat of the'wheeland provided with extending diagonally a plurality of ribs across thethroatof the wheel.

5. A brake shoe comprising a flange engaging portion, a rim intermediateportion cut back to avoid contact with the throat of the Wheel andaplurality of ribs on the back of the shoe opposite the cut awayportion.

6. A brake shoe comprising a flange engaging portion, a rim en agingportion, an intermediate portion cut ack to avoid contact with thethroat of the wheel, a plurality of ribs partially bridging the cut backportion, and a plurality of ribs on the back of the shoe opposite thecut away portion.

7. A brake shoe comprising a flange engaging portion, a rim en agingportion, an intermediate portion cut back to avoid contact with thethroat of the wheeland a plurality of ribs in the 'cut away portion withtheir faces extending diagonally across the throat of the wheel. g

In testimony whereof I have hereunto signed my name in the presence ofthe two subscribing witnesses.

SAMUEL P. BUSH. VVitnessesr PAUL CARPENTER, GERALD IV. CUNNINGHAM.

engaging portion, an

